/*
 * This file Copyright (c) 2015. Walle.
 * (http://www.wallellen.com). All rights reserved.
 *
 *
 * This file is dual-licensed under both the
 * Walle Agreement (WA) and the GNU General Public License.
 * You may elect to use one or the other of these licenses.
 *
 * This file is distributed in the hope that it will be
 * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
 * implied warranty of MERCHANTABILITY or FITNESS FOR A
 * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
 * Redistribution, except as permitted by whichever of the GPL
 * or WA you select, is prohibited.
 *
 * 1. For the GPL license (GPL), you can redistribute and/or
 * modify this file under the terms of the GNU General
 * Public License, Version 3, as published by the Free Software
 * Foundation.  You should have received a copy of the GNU
 * General Public License, Version 3 along with this program;
 * if not, write to the Free Software Foundation, Inc., 51
 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * 2. For the Walle Agreement (WA), this file
 * and the accompanying materials are made available under the
 * terms of the WA which accompanies this distribution, and
 * is available at http://www.wallellen.com/agreement.html
 *
 *
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER
 */

/**
 *
 */
package com.wallellen.wechat.token.server;

import com.wallellen.wechat.token.Ticket;
import com.wallellen.wechat.token.TicketType;

/**
 * 内存控制单例
 *
 * @author <a href="mailto:wallellen@hotmail.com">WALLE</a>
 * @date 2015年1月29日
 */
public class JsApiTicketMemServer implements IServer {

    private static JsApiTicketMemServer ticketServer = new JsApiTicketMemServer();

    private Ticket jsApiTicket = new Ticket(TicketType.jsapi);

    private int requestTimes = 1;//token请求失败后重新请求的次数

    /**
     * 私有构造
     */
    private JsApiTicketMemServer() {
        //获取新的token
        refresh();
    }

    /**
     * token中控服务器实例
     *
     * @return ticket服务器实例
     */
    public static JsApiTicketMemServer instance() {
        return ticketServer;
    }


    /**
     * 通过中控服务器得到accessToken
     *
     * @return
     */
    public String token() {
        //没有可用的token，则去刷新
        if (!this.jsApiTicket.isValid()) {
            refresh();
        }
        return this.jsApiTicket.getToken();
    }

    /**
     * 服务器刷新token
     */
    private void refresh() {
        for (int i = 0; i < requestTimes; i++) {
            //请求成功则退出
            if (this.jsApiTicket.request())
                break;
        }
    }

}
